1. Field of the Invention
This invention relates generally to a method and system of apparatus for cleaning cooling towers and more particularly to a method and system of apparatus which permits cooling towers to be cleaned while continuing in operation.
2. Brief Description of the Prior Art
The use of cooling towers in industry is widespread. Cooling towers circulate water over baffles and permit a portion of the water to evaporate to cool the remainder of the cooling water. Some cooling towers may utilize the water which is used in the plant for cooling, while others utilize the evaporative cooling to cool another material circulated in heat exchange therewith. In both types of cooling tower, there is a problem of contamination by dirt and dust picked up from the air and particulate material brought in with the cooling water. Particulate contaminants collect over a period of time in the basin at the bottom of the tower and from time to time the tower must be shut down to clean out the contaminants which have settled therein. Such a cleaning procedure is costly in terms of down-time for the cooling system and the facility cooled by the cooling tower. Consequently, there has been a need for an inexpensive and efficient method and system of apparatus for cleaning cooling towers while permitting them to continue in operation.
The prior art known to applicant does not disclose the present portable, manned method and apparatus for cleaning cooling towers having a water collection basin at the base while permitting the tower to continue in operation which comprises removing water and particulate contaminants from the bottom of the tower basin by venturi suction or aspiration through a tubular wand having an elongated wide opening to draw in water and particulate matter from a defined area of contact. The suction wand is moved around the bottom of the cooling tower basin to remove water and particulate matter therefrom. The removed water is filtered to separate solid contaminant particles therefrom. The filtrate is by a plurality of screens positioned one above another of successively finer mesh from top to bottom and having a motor for vibrating the screens to remove collected particulate matter therefrom. A collector is positioned adjacent to the ends of the screens to receive the particulate matter discharged by vibration of the screens by the motor. The filtrate is then passed through a plurality of bag filters of successively smaller porosity ranging from about 400 mesh down to about 1 micron to remove fine particles therefrom. Then part of filtrate from the bag filters is recirculated to the cooling tower basin for reuse therein and part is recirculated through the aspirator or venturi to produce a vacuum for withdrawing water and particulate contaminants from the bottom of the tower basin.